Chatgpt:
# don’t own the cloud, rent instead
the “build your own datacenter” story is fun (and comma’s setup is undeniably cool), but for most companies it’s a seductive trap: you’ll spend your rarest resource (engineer attention) on watts, humidity, failed disks, supply chains, and “why is this rack hot,” instead of on the product. comma can justify it because their workload is huge and steady, they’re willing to run non-redundant storage, and they’ve built custom GPU boxes and infra around a very specific ML pipeline. ([comma.ai blog][1])
## 1) capex is a tax on flexibility
a datacenter turns “compute” into a big up-front bet: hardware choices, networking choices, facility choices, and a depreciation schedule that does not care about your roadmap. cloud flips that: you pay for what you use, you can experiment cheaply, and you can stop spending the minute a strategy changes. the best feature of renting is that quitting is easy.
## 2) scaling isn’t a vibe, it’s a deadline
real businesses don’t scale smoothly. they spike. they get surprise customers. they do one insane training run. they run a migration. owning means you either overbuild “just in case” (idle metal), or you underbuild and miss the moment. renting means you can burst, use spot/preemptible for the ugly parts, and keep steady stuff on reserved/committed discounts.
## 3) reliability is more than “it’s up most days”
comma explicitly says they keep things simple and don’t need redundancy for ~99% uptime at their scale. ([comma.ai blog][1]) that’s a perfectly valid trade—if your business can tolerate it. many can’t. cloud providers sell multi-zone, multi-region, managed backups, managed databases, and boring compliance checklists because “five nines” isn’t achieved by a couple heroic engineers and a PID loop.
## 4) the hidden cost isn’t power, it’s people
comma spent ~$540k on power in 2025 and runs up to ~450kW, plus all the cooling and facility work. ([comma.ai blog][1]) but the larger, sneakier bill is: on-call load, hiring niche operators, hardware failures, spare parts, procurement, security, audits, vendor management, and the opportunity cost of your best engineers becoming part-time building managers. cloud is expensive, yes—because it bundles labor, expertise, and economies of scale you don’t have.
## 5) “vendor lock-in” is real, but self-lock-in is worse
cloud lock-in is usually optional: you choose proprietary managed services because they’re convenient. if you’re disciplined, you can keep escape hatches: containers, kubernetes, terraform, postgres, object storage abstractions, multi-region backups, and a tested migration plan. owning your datacenter is also lock-in—except the vendor is past you, and the contract is “we can never stop maintaining this.”
## the practical rule
*if you have massive, predictable, always-on utilization, and you want to become good at running infrastructure as a core competency, owning can win.* that’s basically comma’s case. ([comma.ai blog][1])
*otherwise, rent.* buy speed, buy optionality, and keep your team focused on the thing only your company can do.
if you want, tell me your rough workload shape (steady vs spiky, cpu vs gpu, latency needs, compliance), and i’ll give you a blunt “rent / colo / own” recommendation in 5 lines.
[1]: https://blog.comma.ai/datacenter/ "Owning a $5M data center - comma.ai blog"